Correct Answer: B

Rationale: The correct answer is to take Ferrous sulfate on an empty stomach. This medication is best absorbed when taken 1 hour before or 2 hours after meals. Instructing the client to take it with milk, before bedtime, or with antacids can decrease its absorption and effectiveness.

Correct Answer: D

Rationale: The correct answer is D, Rotavirus vaccine. The series for the Rotavirus vaccine is completed prior to the first birthday as it is only administered to infants less than 8 months of age. This vaccine provides protection against severe diarrhea and vomiting caused by rotavirus infection, which is common in infants and young children.

Correct Answer: A

Rationale: To maximize the effectiveness of nicotine gum, the client should avoid eating or drinking 15 minutes before and while using it. This helps ensure proper absorption of nicotine through the oral mucosa.

Correct Answer: C

Rationale: When administering eye drops, it is essential to instruct the client to drop the prescribed amount of medication into the center of the conjunctival sac. This technique helps ensure proper distribution of the medication and reduces the risk of potential adverse effects. Pressing on the inside corner of the eye is done to prevent systemic absorption, applying drops directly on the cornea can cause irritation, and wiping the eyes after application can lead to decreased effectiveness of the medication.

Correct Answer: A

Rationale: St. John's wort should be avoided by clients taking Warfarin as it can reduce the medication's effectiveness by interacting with its metabolism. While garlic and ginseng are also known to interact with Warfarin, the specific supplement the nurse should instruct the client to avoid in this scenario is St. John's wort.